Fix divisibleBy for small numbers per draft unit tests.

Author: Michael Chiocca

src/JsonSchema/Constraints/Number.php

@@ -53,10 +53,26 @@ public function check($element, $schema = null, $path = null, $i = null)
         }
 
         // Verify divisibleBy
-        if (isset($schema->divisibleBy) && fmod($element, $schema->divisibleBy) != 0) {
+        if (isset($schema->divisibleBy) && $this->fmod($element, $schema->divisibleBy) != 0) {
             $this->addError($path, "is not divisible by " . $schema->divisibleBy);
         }
 
         $this->checkFormat($element, $schema, $path, $i);
     }
-}
+
+    private function fmod($number1, $number2)
+    {
+        $modulus = fmod($number1, $number2);
+        $precision = abs(0.0000000001);
+        $diff = (float)($modulus - $number2);
+
+        if (-$precision < $diff && $diff < $precision) {
+            return 0.0;
+        }
+
+        $decimals1 = mb_strpos($number1, ".") ? mb_strlen($number1) - mb_strpos($number1, ".") - 1 : 0;
+        $decimals2 = mb_strpos($number2, ".") ? mb_strlen($number2) - mb_strpos($number2, ".") - 1 : 0;
+
+        return (float)round($modulus, max($decimals1, $decimals2));
+    }
+}

tests/JsonSchema/Tests/Constraints/DivisibleByTest.php

@@ -73,6 +73,22 @@ public function getValidTests()
                         "value": {"type": "number", "divisibleBy": 1.5}
                     }
                 }'
+            ),
+            array(
+                '{"value": 0.0075}',
+                '{
+                    "properties": {
+                        "value": {"type": "number", "divisibleBy": 0.0001}
+                    }
+                }'
+            ),
+            array(
+                '{"value": 1}',
+                '{
+                    "properties": {
+                        "value": {"type": "number", "divisibleBy": 0.02}
+                    }
+                }'
             )
         );
     }